Managing Tight Binding Receptors for New Separations Technologies

This program is directed at establishing the fundamental principles that will make the most strongly binding ligands and their complexes available to separations technologies.The ultimate powerful ligands can capture metal ions in the most competitive of circumstances. Ultra tight-binding ligands can remove metal ions from mineralized sites, take them away from lesser ligands, and even capture metal ions from extremely dilute solutions. Further, these feats offer the possibility of solving some of the most serious environmental challenges that cannot be met by existing technologies: decontamination of metal surfaces, removal of metal contaminations from soils, separation of very low concentrations of radioactive metal ions from nuclear waste, capturing of contaminating metal ions from extremely dilute solutions. Despite their promise, extremely stable complexes are rarely used in separations because their great stabilities are accompanied by very slow rates of complex formation and dissociation. Specifically, this program has attacked this limitation in two ways: (1) seeking ba sic scientific ways of overcoming the natural molecular lethargy of ultra tight-binding ligands and (2) developing a new technology that functions despite the slowness of the metal binding reactions. The three basic concept areas of this program are: replace slow equilibrium formation and dissociation of ultra tight-binding complexes by (1) switch-binding of templating ligands, and (2) switch-release of photo reactive ligands, and (3) Create a slow separations technology based on imprinted polymers (e.g., a soil poultice)

Liquid CO2 as a safe and benign solvent for the ozonolysis of fatty acid methyl esters

We have shown that liquid CO2 dissolves O3 in higher concentrations compared to conventional solvents and is therefore an effective medium for the ozonolysis of unsaturated compounds. The Beer–Lambert law extinction coefficient for ozone in liquid CO2 is determined to be 3.2 ± 0.3 M–1 cm–1. Further, the Henry’s law coefficient for ozone dissolution in dense phase CO2 is determined to be on the order of 0.25 mol L–1 bar–1 in the temperature range −10 to +4 °C. Rapid ozonolysis of methyl oleate in liquid CO2 has been successfully demonstrated with the 1,2,4-trioxolanes (secondary ozonides) being the major stable product, as confirmed by NMR analysis. The product distribution is consistent with a lack of solvent cage effects due to the low polarity of liquid CO2. In addition to the inertness of liquid CO2 to ozone attack, the dominant presence of dense CO2 in the vapor phase promotes inherent process safety

Guidelines for the use of flow cytometry and cell sorting in immunological studies

International audienceThe classical model of hematopoiesis established in the mouse postulates that lymphoid cells originate from a founder population of common lymphoid progenitors. Here, using a modeling approach in humanized mice, we showed that human lymphoid development stemmed from distinct populations of CD127(-) and CD127(+) early lymphoid progenitors (ELPs). Combining molecular analyses with in vitro and in vivo functional assays, we demonstrated that CD127(-) and CD127(+) ELPs emerged independently from lympho-mono-dendritic progenitors, responded differently to Notch1 signals, underwent divergent modes of lineage restriction, and displayed both common and specific differentiation potentials. Whereas CD127(-) ELPs comprised precursors of T cells, marginal zone B cells, and natural killer (NK) and innate lymphoid cells (ILCs), CD127(+) ELPs supported production of all NK cell, ILC, and B cell populations but lacked T potential. On the basis of these results, we propose a "two-family" model of human lymphoid development that differs from the prevailing model of hematopoiesis

Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry

IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes